The present invention relates to a method of preserving natural perishable products by dispersing ozone throughout a substantially closed room containing said natural perishable products.
The purification of environments can be achieved through the use of ozone. Ozone has been used to purify air conditioning systems in buildings and to sanitize warehouses where products are stored. Despite its widespread use, this basic technique has the disadvantage of accumulating more ozone than is necessary in the treated environment, requiring the elimination of the excess ozone. Several different improvements in this method have been made in an attempt to control the levels of ozone in the environment being treated. One such improvement provides high initial levels of ozone to the environment sufficient to produce the desired bacteriostatic or bacteriocidal effect. Later the levels of ozone are reduced so that they do not produce harmful effects to the products being treated or to humans.
The majority of the known systems for purifying substantially closed areas with ozone are based on an ozone generator that utilizes a source of concentrated oxygen. When ozone is generated from a source of concentrated oxygen, the level of oxygen in the enclosure rises along with the level of ozone. The increase in oxygen levels is due to the breakdown of ozone into new molecules of oxygen. An increase in the level of oxygen in enclosures containing natural perishable products enhances cellular metabolism and thus is detrimental to the storage of the perishable products.
The method of the present invention is rather simple, but produces unexpected beneficial effects compared to the state of the art methods. The method of the present invention is applied to substantially closed rooms or rooms with a controlled atmosphere. A substantially closed room is a room that is closed but not necessarily air-tight. The substantially closed room may have a closed circuit air conditioning system, such as a cooling system, for the preservation of perishable natural products. A known ozone generator is placed in proximity with the substantially closed room such that the ozone generator can draw in air from the substantially closed room and liberate ozone into the substantially closed room. The generated ozone may be delivered into the substantially closed room through the action of the air conditioning system. The ozone thus enters the atmosphere of the closed room along with the conditioned air. In this way the design characteristics of the air conditioning system are taken advantage of so that the ozone is efficiently distributed throughout the volume of the room.
In contrast to known ozonation systems, the present invention utilizes oxygen from the air of the room in which the purification treatment is being applied. Because the present invention converts oxygen from the air into ozone, no increase in oxygen levels is observed in the closed room. Rather, the gaseous equilibrium is shifted so that there is a decrease in the level of oxygen in the enclosure. Thus when the method of the present invention is applied, the oxygen levels in the enclosure tend to go down initially and then return partially as breakdown products of ozone generate new molecules of oxygen. This overall reduction in oxygen levels helps with the preservation of perishable natural products stored in the closed room by reducing cellular metabolism.
Additionally, the method of the invention can be used with sensors for temperature, humidity and ozone concentration. This allows the user to optimize the level of ozone generation depending on the special characteristics of the perishable food products. This can be done manually or automatically. However, dynamic control systems are not needed with the present method.